Mithril & Mud

Mithril & Mud is an idle mining game about a hold of cheerful, stubborn dwarves who dig too deep. You begin with one ore vein and a pickaxe, click the vein, hire Dwarf Miners and build rooms around the cave. As the hold grows, carts run along the tracks and the tavern fills, while your dwarves look for the next tunnel to dig.

Dig deeper

Each descent costs more and pays more. Cave-ins block tunnels, while trolls and Lithodore the dragon raid the hold. Your Runic Warriors fight them; after you forge the Runic Warblade, you can also click a raider to strike it yourself.

The main dig ends at depth 20, where you can forge a crown. Beyond that, tunnels continue through four biomes: the Emberdeep, the Drowned Halls, the Crystal Choir and the Hollow Dark. Each biome changes one rule—more mithril, faster expeditions, more cave-ins or more raids—and gives the ore vein a different look. A Warden appears halfway through each biome; defeating it earns a trophy relic. From depth 60, the biomes repeat and become tougher each time.

Build the hold

Thirteen rooms open as you dig, from the Surveyor's Office and Lumber Mill to the Runic Workshop and the Dark Forge. Assign workers and turn ore into blueprints, timber and mithril. You can also send expeditions to eight destinations and tame beasts at the Beast Den for extra bonuses.

Automate the work

Automation is earned by meeting checklists, not bought. The Foreman, Overseer, Quartermaster, Smeltmaster and Depth Charter each take a job off your hands when they sign on. You can switch them on or off, save profiles or pause them all at once.

The Ancestral Engine is the last helper to unlock. Set a dig-completion target using Ancestral Knowledge or depth, and it starts a New Dig for you, keeps your last challenge and can spend Knowledge on Blessings.

Forge and collect

Craft artifacts, cut gems and forge Mythic Upgrades. Find relics on expeditions and from Wardens, slot runestones and spend Rune Shards on skill tree nodes. Your collection appears on two display shelves in the cave, which gain a plank as it grows.

Trade with nations

The Trade Post lets you trade with ten nations, each with its own embassy in the cave. Higher tiers provide bigger bonuses and require a small amount of Trade Point upkeep each hour; you choose which nations get paid first. You can also hire mercenaries or buy an embargo when needed.

Heroes and Kings

Twelve named dwarves join the Hall of Heroes after you complete their deeds, such as breaking 250 cave-in walls or earning a Gold medal. You can seat up to three at a time. Each changes one rule while seated, from room costs to offline time, and grows stronger through service.

Each Warden holds an old King of its biome. Free the Kings, and after your first Ascension one can sit on a carved stone chair by the campfire. Heroes and Kings remain with you through every New Dig and Ascension.

New Digs and Ascension

When progress slows, start a New Dig to earn Ancestral Knowledge and spend it on Blessings, permanent bonuses that continue levelling beyond their listed maximum. Ascension resets further and adds a second layer of permanent perks.

Omens and challenges

Before each dig, the elders read the stones. Choose one of three omens, each trading an advantage for a disadvantage, or dig without one. There are 14 omens to find.

You can also take on five challenges, each with Bronze, Silver and Gold medals. Medals teach your helpers new upgrades, and a Gold medal adds a banner to the cave ceiling.

Idle and active play

The hold keeps working while the game is closed. Offline progress is counted at your full rate for up to 12 hours, with some omens, relics and heroes extending that time. A Welcome Back report shows what your dwarves did. Clicking the vein and striking raiders also earn rewards while you are playing at the keyboard.

Key features

• 71 Steam achievements, including reaching depth 70, defeating every Warden five times, having all ten nations at Tier 15 at once and filling both shelves; four achievements are hidden.
• Minimal UI, toggled with F8, reduces the screen to icons and numbers, while Calm HUD keeps small pop-ups in the log.
• Colorblind mode, options to reduce screen shake and flashes, rebindable keys, UI scaling and scientific notation.
• Steam Cloud saves, three save slots, save export and import, and an in-game music player.